Conventionally, automatic water faucet devices that automatically discharge water when an object to be detected such as a human body is detected by a sensor are known (for example, refer to Patent Document 1). In a hand wash basin to which such an automatic water faucet device is applied, water (dirty water) containing dirt generated by hand washing flows in a bowl and a perforated plate, and when a period when water is not discharged from the automatic water faucet device (that is, a period when an object to be detected is not detected by a sensor) lasts long, such dirt is dried and stuck in a state of being adhered to the bowl and the perforated plate, and the dirt is hard to be removed. In order to prevent this, before the adhered dirt is dried and stuck, water should be discharged again. For example, Patent Document 2 proposes a technique in which existence of a human body is detected, and thereafter discharging water from a sink washing port for a fixed time after no human body is detected, to keep a sink clean and neat.